Yapped will try to load the regulation from the default Steam location when it starts. If you have the game installed somewhere else, use File->Open to find Data0.bdt in your game directory.
The different params will be displayed in the left pane. Clicking one will display the rows within it in the center pane. Clicking a row will display its values in the right pane.
Rows can be created or deleted from the Edit menu, or with the hotkeys indicated there. By default you will be prompted when deleting a row; uncheck the option in the Edit menu if you don't want that.
Row ID and name can be edited at will; the name has no functional significance. Vanilla DS3 has its row names stripped out; use Edit->Import Names to populate them with names from the network test (which aren't necessarily accurate) and names inferred from text files (which are).
Be aware of the type when editing values. If you enter an invalid value you will receive an error; either correct it, or press Escape to cancel. Types are described below.
